The 1971 Subaru FF-1 came from an era when small imported cars were winning buyers with efficiency, compact packaging, and a more modern engineering approach than many economy cars of the day. For enthusiasts and restorers, it stands apart as an early Subaru with distinctive character and a tire fitment story that reflects that transition period. This model uses two primary 13-inch tire formats: a 6.15-13 bias-ply and a 155R13 radial. That gives owners a clear choice between a more traditional bias-ply presentation and a period-style radial setup from brands such as Michelin and Dunlop. The right decision depends on whether appearance, driving feel, and wheel compatibility matter most for the car being preserved or driven.
Which Tire Size Is Right for The 1971 Subaru FF-1
The 1971 Subaru FF-1 uses two primary tire sizes, and both fit a 13-inch rim. The choice is less about sub-model differences and more about construction, since both the Sedan and Wagon use the same bias-ply 6.15-13 and radial 155R13 formats. The first step is deciding whether the car should stay with a traditional bias-ply style or use a period-appropriate radial tire.
155R13 is a Euro-metric radial size in which 155 represents the nominal section width in millimeters, R identifies radial construction, and 13 is the rim diameter in inches. On the 1971 Subaru FF-1, this size reflects the car's more modern tire option and keeps the fitment on the original 13-inch wheel diameter. Available choices include blackwall radial tires from Michelin and Dunlop, with series such as Michelin XAS-FF and SP Sport Aquajet. This size makes sense for owners who want a period-style radial presentation and who are checking wheel width and overall setup carefully before selection.
6.15-13 is a numeric bias-ply size, with 6.15 indicating the nominal section width in inches and 13 identifying the wheel diameter. For a 1971 Subaru FF-1, this size represents the traditional bias-ply fitment and suits buyers who want to stay closer to an earlier driving character and vintage tire appearance. Bias-ply construction also changes the selection focus, since the decision is usually about preserving period style rather than comparing multiple modern radial series. This size is worth evaluating when restoration goals and original-style presentation matter more than moving to a radial format.
Tire fitment is straightforward across the covered 1971 Subaru FF-1 sub-models, because both the Sedan and Wagon use the same two primary 13-inch tire sizes. Checking the exact sub-model still helps confirm the car's setup, especially if wheels or tires may have been changed over the years.
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1971 Subaru FF-1 Sedan
The 1971 Subaru FF-1 Sedan uses the same two primary tire choices as the broader model range: 155R13 radial and 6.15-13 bias-ply. That means the main decision is whether the car should keep a traditional bias-ply look or move toward a period-style radial tire on the same 13-inch wheel diameter.
The 1971 Subaru FF-1 Wagon shares the same 155R13 radial and 6.15-13 bias-ply fitment used on the Sedan. Tire selection therefore centers on construction choice, appearance, and wheel compatibility rather than a separate Wagon-specific tire size.
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Best 1971 Subaru FF-1 Tires for Sale
Available 155R13 radial options for the 1971 Subaru FF-1 come from Michelin and Dunlop in blackwall form, with period-oriented series such as Michelin XAS-FF and SP Sport Aquajet. These choices give buyers useful comparison points in brand, series character, and rim-width compatibility.
Common questions for the 1971 Subaru FF-1 usually center on choosing between 6.15-13 bias-ply and 155R13 radial tires, confirming 13-inch wheel fitment, and deciding which available radial products best suit restoration or road use.
Tire Size & Fitment
What tire size fits a 1971 Subaru FF-1?
The 1971 Subaru FF-1 uses two primary tire sizes: 155R13 in radial construction and 6.15-13 in bias-ply construction. Both sizes are associated with the model, and both the Sedan and Wagon use the same fitment choices rather than separate sub-model-specific sizes.
That means the real decision is not which sub-model size applies, but which construction best suits the car. A bias-ply 6.15-13 keeps a more traditional vintage presentation, while a 155R13 radial follows a more modern sizing format. Before choosing either one, confirm that the wheels on the car are still 13-inch wheels and have not been replaced during past service or restoration work.
What size rim does a 1971 Subaru FF-1 use?
The 1971 Subaru FF-1 uses a 13-inch rim diameter with both of its primary tire sizes. That applies whether the car is fitted with a 6.15-13 bias-ply tire or a 155R13 radial tire, since both sizes are built around the same wheel diameter.
Rim diameter is only part of the fitment picture, so it is still smart to verify the actual wheel width on the car before selecting tires. Collector vehicles are often changed over time, and a replacement wheel can affect how a tire sits and performs. A tire can have the correct 13-inch diameter and still need a wheel width that matches its intended mounting range.
Do all 1971 Subaru FF-1 sub-models use the same tire size?
Yes. The 1971 Subaru FF-1 Sedan and Wagon both use the same two primary tire sizes: 155R13 radial and 6.15-13 bias-ply. There is no separate tire size split between those two sub-models, so the fitment stays consistent across the range covered here.
That consistency makes the buying process simpler, but it does not remove the need to inspect the individual car. An FF-1 that has spent decades on the road may have different wheels, altered suspension height, or simply a mismatched set of older tires. Confirming the current wheel setup and deciding whether the goal is period-style bias-ply appearance or radial road use will lead to a more confident tire choice.
Choosing the Right Tire
What should I consider when choosing a 155R13 or 6.15-13 tire for a 1971 Subaru FF-1?
Start with the correct primary size and construction for the way the car will be used. The 1971 Subaru FF-1 accepts either a 6.15-13 bias-ply tire or a 155R13 radial, so the key choice is whether the car should retain a more traditional bias-ply feel or use a period-style radial format.
After that, look at the actual wheel setup, especially if the car has been restored or modified over the years. A radial option such as 155R13 may also involve comparing brand, tire series, and rim-width suitability. For a low-use collector car, appearance and authenticity of presentation may lead the decision, while a regularly driven FF-1 may push the choice toward a radial tire.
What sidewall styles are available for 1971 Subaru FF-1 tires?
The available 155R13 radial products for the 1971 Subaru FF-1 are offered in blackwall form. That gives the radial side of the fitment a clean, understated period presentation rather than a whitewall or striped sidewall treatment.
Sidewall style matters because it changes the car's visual character even when the tire size stays the same. A blackwall radial can suit an FF-1 with a simple, driver-oriented look, especially on a preserved or lightly restored car. If appearance is a major part of the decision, compare the tire's construction and overall presentation with the look you want before settling on a radial or bias-ply direction.
What brands offer tires for the 1971 Subaru FF-1?
For the 155R13 radial fitment on a 1971 Subaru FF-1, available brands include Michelin and Dunlop. Those products appear in period-oriented radial series such as Michelin XAS-FF and Dunlop SP Sport Aquajet, giving buyers more than one established brand choice within the correct size category.
Brand alone should not decide the tire. It is better to compare the full package, including the correct size, radial construction, sidewall style, rim-width suitability, and the overall look you want on the car. If the FF-1 still has its original-style wheel setup, a period-appropriate radial series can be a strong match, but the final selection should still reflect how the car will be driven and presented.
Restoration & Appearance
Which tire should I choose for a period-style 1971 Subaru FF-1?
A period-style 1971 Subaru FF-1 can be approached in two different ways, depending on the look and driving character you want to preserve. The 6.15-13 bias-ply size leans toward a more traditional vintage presentation, while the 155R13 radial reflects the small imported-car transition into more modern tire construction during the era.
That choice usually comes down to whether the car is being restored for authenticity of appearance, road use, or a balance of both. If exact originality matters, it helps to compare the tire selection against marque references, period photography, or other vehicle-specific historical material. For many owners, keeping the right size and a suitably period-style overall look is the practical starting point.
How does tire construction affect the appearance of a restored 1971 Subaru FF-1?
Tire construction changes both the stance and visual character of a restored 1971 Subaru FF-1. A 6.15-13 bias-ply tire supports a more traditional vintage look, while a 155R13 radial gives the car a later, more modernized small-import appearance even when the wheel diameter remains the same.
That difference matters because tires are one of the most visible details on a compact car with relatively small wheels. A blackwall radial such as the available 155R13 choices can still look very appropriate, but it presents the car differently than a bias-ply setup. For restoration-minded owners, the best choice is the one that matches the intended era, wheel style, and overall presentation of the finished vehicle.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1971 Subaru FF-1?
Yes. Even though the 1971 Subaru FF-1 uses 13-inch tire fitments, modifications can change how well a tire works on the car. Aftermarket wheels, different wheel widths, altered ride height, suspension repairs, or body changes can all affect clearance and the way either a 155R13 radial or 6.15-13 bias-ply sits in the wheel opening.
That is especially important with older imported cars, because many have been repaired or updated over time. A tire in the correct nominal size still needs to work with the actual wheel and the car's present condition. Check steering clearance, fender space, and wheel dimensions before making a final choice, particularly if the car no longer wears its original-style wheels.
What should I inspect before driving a 1971 Subaru FF-1 on new tires?
Before putting a 1971 Subaru FF-1 back on the road with new tires, inspect the wheels, valve stems, and the overall condition of the suspension and steering. It is also wise to make sure the tires are mounted on the correct 13-inch wheels and that there is no visible interference at full steering lock or normal ride height.
A collector car that has been parked for long periods deserves extra attention beyond the tires themselves. Look for brake drag, worn suspension bushings, loose wheel hardware, and any sign that the old tires were rubbing or losing air. After installation, monitor pressure and recheck the car after the first few drives so any clearance or mounting issue is caught early.
How should 155R13 and 6.15-13 tires on a collector 1971 Subaru FF-1 be maintained?
Tires on a collector 1971 Subaru FF-1 should be inspected regularly for cracking, bulges, cuts, uneven wear, and air loss, even if the car is driven only occasionally. That applies equally to 155R13 radial tires and 6.15-13 bias-ply tires, since age and storage conditions matter as much as mileage on a low-use vintage vehicle.
Proper inflation, clean storage, and periodic movement of the car all help preserve tire condition. Keep the FF-1 away from prolonged sunlight, excess heat, and ozone sources such as running electric motors when possible. It also helps to look over the tires before every meaningful drive, because older collector cars can sit for months and develop problems that are easy to miss until the car is back on the road.
